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VULNERABILITIES

CVE-2026-113603 Details

Description

The x402 SIWX server extension in @x402/extensions 2.3.1 through 2.28.0, x402 PyPI 2.11.0 through 2.25.0, and Go module 2.16.0 through 2.28.0 contains an authorization bypass vulnerability that allows paying clients to unlock unpaid routes by supplying a mismatched PaymentPayload.resource URL. Attackers can pay for the cheapest SIWX-protected route while setting resource.url to an expensive route, then repeatedly access it using only a SIGN-IN-WITH-X header without further payment.

Metrics

CVSS 3.x Severity and Vector Strings:

References to Advisories, Solutions, and Tools

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Weakness Enumeration

CWE-IDCWE NameSource
CWE-639Authorization Bypass Through User-Controlled Key[email protected]

Affected Products

No affected product data is available for this CVE.

Change History

2 change records found show changes


QUICK INFO

CVE Dictionary Entry:
CVE-2026-113603
NVD Published Date:
Oct 20, 2026
NVD Last Modified:
Oct 21, 2026
Source:
[email protected]
CVE-2026-113603 Details - Not Deferred